Publishing Events though MQTT API

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Publishing Events though MQTT API

jaspernp

When you publish events through the MQTT API they should appear should they appear under the Events window

Iv tried publishing to
- events
- devices/{myDeviceId}/events

However I never see any events come through. I have connected through the secure and non secure MQTT ports with the same result.

I also find that the handlers such as CONNECTED is not firing even though my devices confirms a connection to the MQTT server as it never moves from LISTENING FOR DEVICE under CONFIGURATION

The only way iv managed to publish events and see handlers is the cURL API.

I think its something to do with part of the documentation
"To communicate with the Wia MQTT API an access token is required"

The documentation then doesn't go into any detail about how this is to be passed to the MQTT API. Currently I am just connecting to the MQTT server with the device key and a blank space as the password but this does not seem to be enough.

Can someone please point out how an access token is to be used with the MQTT API and what to do with token once its generated.

Thanks

conall

Hey,
What type of device are you trying to connect to the MQTT API? The setup should be as follows:
Endpoint: One of either mqtt.wia.io:1883 or mqtt.wia.io:8883
Username: Device secret key - This is generated in the Wia dashboard when you create a device. Go to the Device's Configuration page to find it, it should begin with d_sk.
Password: Empty space

For the topic, use either events or devices/{DEVICE_ID}/events/{EVENT_NAME} e.g. devices/dev_abc123/events/humidity. You can find your device ID in the configuration page also, it should begin with dev_.

For the payload, it should be a JSON object with both name and data parameters. It should look like this:

{
 "name": "humidity",
 "data": 67
}

To check if everything is working ok, go to the Debugger for your Device, this too is in the Device page. You should see the Event coming through.

manfred

I was able to send events by the MQTT.fx client app.
But sending events by an Quectel BG96 module (NB-IoT) did not work,

In the "BG96_MQTT_Application_Note_V1.0" ( https://sixfab.com/wp-content/uploads/2018/09/Quectel_BG96_MQTT_Application_Note_V1.0.pdf ) there is an example for publishing by the command AT+QMTPUB:
AT+QMTPUB=0,0,0,0,“topic/pub”

This is test data, hello MQTT

What do i have to send instead of "This is test data, hello MQTT" for updating the value of the key "name"? I send {"name": "nb-iot","data": "testing"}. I get an "OK +QMTPUB: 0,0,0" response but no event arrives at wia.io. What is wrong?

alanWia

Hey @manfred, we haven't tried MQTT over NB-IoT, have you made any headway it? if so, can you share your experiences?

manfred

After some more experiments by manually sending AT commands over terminal software i found out that it works very simple.

First preset your BG95-G for AUTOCONNECT by the following commands, that work with Vodafone Germany
AT+NCONFIG=AUTOCONNECT,TRUE
AT+NCONFIG=CR_0354_0338_SCRAMBLING,TRUE (depends on your carrier?)
AT+NCONFIG=CR_0859_SI_AVOID,FALSE (depends on your carrier?)
AT+NBAND=20 (depends on your country and carrier!)
AT+CGDCONT=0,“IP”,“nb.inetd.gdsp” (Vodafone, “0” is belonging to AUTOCONNECT)
AT+COPS=0

After the “AT+NRB” reset command these preferences are stored in the NV-RAM of the BC95-G and used for AUTOCONNECT at startup.

Next you see the typed in commands an the response:

at+cfun=1

OK
AT+QMTOPEN=0,"api.wia.io",1883

OK
+QMTOPEN: 0,0
AT+QMTCONN=0,"xyz","d_sk..."
OK
+QMTCONN: 0,0,0
AT+QMTPUB=0,0,0,1,"devices/dev..."

{"name":"NB-IoT"}
Ctrl+Z
OK
+QMTPUB: 0,0,0

AT+QMTPUB=0,0,0,1,"devices/dev_..."

{"name":"NB-IoT"}
Ctrl+Z
OK
+QMTPUB: 0,0,0

Hint: you have to use the "d_sk..." and "dev..." of your device